STM32L071X8 datasheet(22/136 Pages) STMICROELECTRONICS

Numer części	STM32L071X8

Szczegółowy opis	Access line ultra-low-power 32-bit MCU ARM-based Cortex-M0, up to 192KB Flash, 20KB SRAM, 6KB EEPROM, ADC

PDF	136 Pages

Scroll/Zoom	100%

Producent	STMICROELECTRONICS [STMicroelectronics]

Strona internetowa	http://www.st.com

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22 / 136 page

Functional overview

STM32L071xx

22/136

DocID027101 Rev 3

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32.768 kHz low-speed external crystal (LSE)

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37 kHz low-speed internal RC (LSI), also used to drive the independent watchdog.

The LSI clock can be measured using the high-speed internal RC oscillator for

greater precision.



RTC clock source

The LSI, LSE or HSE sources can be chosen to clock the RTC, whatever the system

clock.



Startup clock

After reset, the microcontroller restarts by default with an internal 2.1 MHz clock (MSI).

The prescaler ratio and clock source can be changed by the application program as

soon as the code execution starts.



Clock security system (CSS)

This feature can be enabled by software. If an HSE clock failure occurs, the master

clock is automatically switched to HSI and a software interrupt is generated if enabled.

Another clock security system can be enabled, in case of failure of the LSE it provides

an interrupt or wakeup event which is generated if enabled.



Clock-out capability (MCO: microcontroller clock output)

It outputs one of the internal clocks for external use by the application.

Several prescalers allow the configuration of the AHB frequency, each APB (APB1 and

APB2) domains. The maximum frequency of the AHB and the APB domains is 32 MHz. See

Figure 2 for details on the clock tree.

STM32L071X8 Arkusz danych(PDF) 22 Page - STMicroelectronics